Studies Show a Link Between Hearing Loss and Cognitive Decline

Yet another article has been published describing the impacts of untreated hearing loss. The findings in the study link hearing loss and cognitive decline, and the CBC has made an easily digestible summary from their radio program earlier this month by Dr. Peter Lin. Harvard Medical School followed 10 000 men over 8 years and were able to compare those with hearing loss and those with normal hearing. The participants in the study used subjective cognitive decline, or memory and thinking problems they noticed themselves. This means the changes noted were more subtle, and involved with earlier signs of cognitive change, and not necessarily a full diagnosis of dementia.

The Take Home Message? Untreated Hearing Loss and Cognitive Decline Seem to be Related

The take home message of the study was that men with mild hearing loss had a 30% increased risk of subjective cognitive decline, men with moderate hearing loss had a 42% increased risk of subjective cognitive decline, and those with severe hearing loss had a 54% increased risk of subjective cognitive decline!

How Does Untreated Hearing Loss Lead to Increased Cognitive Decline?

Reasons listed in the article as to why hearing loss leads to increased risk of cognitive decline include:

Trouble hearing leads to increased strain: when it is hard to hear, a person will concentrate harder and use more resources from other areas to hear – this could mean the resources are no longer available for things like memory

Nothing to process: when a person lacks normal hearing, there is less information for the auditory cortex (the part of the brain responsible for hearing) to process, and with this lack of ‘work’, that part of the brain can start to shrink. Surrounding areas that support the auditory center of the brain can also start to shrink.

Isolation: when it is too hard to hear at a social gathering or social activity, people may choose not to go, which leads to the entire brain not being stimulated. As a result, there is less for the brain to do, and this is also linked to parts of the brain shrinking.

There is some good news though. Those with severe hearing loss who wore hearing aids were able to reduce future memory loss by 37%, which highlights the importance of keeping your brain stimulated (even after a deficit period) and staying engaged socially!